The standard means of providing auxiliary heat to a bed is an electrically powered blanket. To a lesser degree, where only localized heat is desired, electrically powered heat pads are used.
Electrical blankets are employed over one's person and provide a warming effect by virtue of one's proximity to the blanket. Typically, there is only a sheet separating one from the blanket. It is, of course, recognized that as heat rises, this is not an optimum relationship, but electrical blankets are not constructed of sufficient durability to provide adequate assurance of their safety if used as an underlay. In any event, as one is instructed to use them, as a cover, one suffers the disadvantage that a principal amount of the heat energy they release rises and is not available for heating one's body. Second, the blankets, as electrical devices, are relatively fragile and typically do not enjoy a long life. Finally, there have been many instances where the blankets have malfunctioned in use and have overheated very substantially. This, in turn, has produced serious danger to users.
The problems recited are particularly unfortunate at this time inasmuch as, unquestionably, electrical blankets can provide personal heat at a much reduced cost over that of a conventional space heating system.
It is the object of this invention to provide a bed heating system which is particularly comfortable to provide bed heating in a room with reduced room temperatures, e.g., 60.degree. F. to 65.degree. F., and to accomplish this in a much safer manner than accomplished by an electrically powered blanket.